Here are some accidental photographs taken from angles that coincidentally make two perspectives possible. Although these do not involve silhouettes, the angles eliminate some of the necessary context clues to arrive at only one visual image, so they unwittingly create the same effect as the spinning dancer. At first glance, you see something, but then realize that there are actually two ways to see it.
However, in this case, there are enough context clues to tell us when we see something wrong. Some people will immediately see the right version, while others will see the little visual trick but then do a double take because the information clashes with what they have learned about the world.
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